It was an interesting question! So, although Orsinia-san has already answered you beautifully, I worked out another expression. なっとうは、「なれる（慣れる）とクセ(癖）になる」食べ物かもしれません。 Natto could be addictive when a person gets used to it.

It’s hard to find a specific word exactly fit for “acquired taste.” My dictionary says like; acquired taste: 次第に好きになる味 (taste you come to like it gradually.) I know that is not what you want. :) I'd like to try to show you some examples: わたしはだんだん納豆の**味がわかる**ようになりました。 I have acquired a taste for natto. 香菜は**好きな人にはわかる味**です。 Coriander leaf is an acquired taste. (cf. Many Japanese dislike its flavor.) アイリッシュウィスキーは**大人の味**です。 Irish whisky is an acquired taste. 梅干しは私には**慣れ親しんだ味**です。 (なれしたしんだ) Umeboshi, a kind of awfully sour pickled plum, is an acquired taste for me. (I’ve gotten used to taste umeboshi and love it now.) Could this help you a bid?

I couldn't find any good translations but Orsinia-san did it perfectlly. I learned from your question and her answer, thank you so much!

I am lookin' at you nattō...